Ablation of molecular solids under nanosecond laser pulses: The role of inertial confinement

The thermal routes to ablation in molecular solids having a long (micron scale) optical penetration depth are investigated under nanosecond laser pulses using a two-dimensional molecular-dynamics model. The authors demonstrate that the mechanisms of matter removal are mainly determined by the local degree of inertial confinement; by increasing level of confinement, these are (trivial) fragmentation, phase explosion, and heterogeneous nucleation of vapor bubbles at solid-liquid boundaries. The thermodynamic pathways to ablation are shown to be different from those predicted by the model of Miotello and Kelly [Appl. Phys. Lett. 67, 3535 (1995); Appl. Phys. A: Mater. Sci. Process. 69, S67 (1999)]. (c) 2006 American Institute of Physics. [DOI: 10.1063/1.2358941]